Ferrule push

ABSTRACT

A fiber optic ferrule push includes a main body extending between a front end and a rear end, the main body having a central opening extending between the front end and the rear end to receive a plurality of optical fibers therethrough, a front facing surface configured to engage a rear surface of a fiber optic ferrule, and at least one projection extending outward from the main body to engage a housing configured to receive the fiber optic ferrule, the fiber optic ferrule push may also include a key extending outward from a surface of the main body. The fiber optic ferrule push may be paired with a fiber optic ferrule in a fiber optic assembly.

REFERENCE TO RELATED CASE

This application claims priority under 35 U.S.C. § 119 (e) to U.S.provisional application No. 62/901,636 filed on Sep. 17, 2019, thecontents of which are hereby incorporated by reference in theirentirety.

BACKGROUND OF THE INVENTION

In a data center environment, the routing of optical fibers between datacenters usually requires the connection of thousands of optical fibersto connect one data center building to another. Such connections involvemanually fusion splicing several thousands of optical fibers. Thesplicing is usually the last job before the connection of the datacenters is complete. However, manually splicing optical fibers is timeconsuming and expensive due to the labor costs and equipment needed forthe job. Thus, this job becomes the bottleneck for bring the new datacenters on-line.

A solution to avoiding the fusion-splicing includes using pre-terminatedMT ferrules in a pulling grip (or “pulling sock”) attached to a jacketedcable between the two datacenter buildings. Such a pulling grip is knownin the art. Depending on how many fibers per fiber optic ferrule arepresent, the number of fiber optic ferrules inside the pulling grip willvary. For example, one pulling grip may accommodate a total of 3456fibers in 288 fiber optic ferrules (i.e., each ferrule having 12fibers). These fiber optic ferrules are then pulled out of the pullinggrip at a designated spot inside the second data center building.Subsequently, an MT-MPO adapter, such as the one shown in U.S. Pat. No.7,296,935 owned by the Applicant, may be used to connect an MT ferruledirectly to an MPO style connector. One concern with this approach isthat a technician/user at the data center will need to handle a bare,terminated fiber optic ferrule. This increases the chances of damage tothe ferrule, especially since there are hundreds of such fiber opticferrules that need to be inserted into MT-MPO adapters. Further, on theother side of the adapter, an MPO connector is typically alreadyinstalled and when the bare fiber optic ferrule is installed with theoptical fiber ribbon, subjecting the fiber optic ferrule to high forces(up to around 20N). These forces make it a bit difficult to plug in thefiber optic ferrule. While the MT-MPO adapter solution is highlydesirable in many other applications involving a relatively smallernumber of connections, this solution, though feasible, is not optimal.An MPO-MPO adapter may alternatively be used. However, MPO connectorsare larger and may not fit inside a cable or a pulling grip attached tothe cable connecting two data centers due to their size. Further, theuse of MPO connectors increases the footprint on the panel on whichother connectors are placed.

Thus, there is a need for a solution to a bulky connector being pulledthrough conduits to connect the data centers.

SUMMARY OF THE INVENTION

The present invention is directed to a fiber optic ferrule push thatincludes a main body extending between a front end and a rear end, themain body having a central opening extending between the front end andthe rear end to receive a plurality of optical fibers therethrough, afront facing surface configured to engage a rear surface of a fiberoptic ferrule, at least one projection extending outward from the mainbody to engage a housing configured to receive the fiber optic ferrule,and a key extending outward from a surface of the main body.

In some embodiments, the front facing surface is a first front facingsurface and the front end of the fiber optic ferrule push has a secondfront facing surface, the second front facing surface disposed parallelto and rearward of the first front facing surface.

In some embodiments, the front end has at least one receptacle toreceive a portion of a guide pin disposed within a fiber optic ferruleassociated with the fiber optic ferrule push.

In other embodiments, the main body has a slot in one surface, the slotextending from the front end to the rear end.

In yet another aspect, there is a fiber optic assembly that includes afiber optic ferrule push and a fiber optic ferrule, the fiber opticferrule push further includes a main body extending between a front endand a rear end, the main body having a central opening extending betweenthe front end and the rear end to receive a plurality of optical fiberstherethrough, a latch disposed on one of a housing and the main body,the latch to engage a surface on the other of the housing and the mainbody, a first alignment structure to engage a corresponding secondalignment structure on the housing to align the fiber optic ferrule pushto the housing, and a front facing surface configured to push on a rearsurface of a fiber optic ferrule, and the fiber optic ferrule furtherincludes a main body having a plurality of optical fiber supportstructures to receive the plurality of optical fibers, and a rear endhaving an opening to receive the plurality of optical fibers, whereinthe opening is less than twice the diameter of the optical fibersinserted therein.

It is to be understood that both the foregoing general description andthe following detailed description of the present embodiments of theinvention are intended to provide an overview or framework forunderstanding the nature and character of the invention as it isclaimed. The accompanying drawings are included to provide a furtherunderstanding of the invention, and are incorporated into and constitutea part of this specification. The drawings illustrate variousembodiments of the invention and, together with the description, serveto explain the principles and operations of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view of one embodiment of a fiberoptic assembly with a cross-section of a housing according to thepresent invention;

FIG. 2 is an enlarged top plan view of the fiber optic assembly in FIG.1 without the housing;

FIG. 3 is an exploded rear side perspective view of the fiber opticassembly in FIG. 1;

FIG. 4 is a front perspective view of the fiber optic ferrule push inFIG. 1;

FIG. 5 is a rear perspective view of the fiber optic ferrule push inFIG. 1;

FIG. 6 is a top view of a cross section of the fiber optic assembly withthe housing in FIG. 1;

FIG. 7 is a top view of the fiber optic assembly in FIG. 1 without thehousing;

FIG. 8 is a top view of a cross section of the ferrule push in FIG. 1;

FIG. 9 is a perspective view of a second embodiment of fiber opticassembly according to the present invention;

FIG. 10 is a bottom perspective view of the fiber optic assembly in FIG.9 without the housing;

FIG. 11 is a perspective view of a third embodiment of a fiber opticassembly according to the present invention;

FIG. 12 is a top perspective view of the fiber optic assembly in FIG.11;

FIG. 13 is a bottom perspective view of the fiber optic assembly in FIG.11;

FIG. 14 is a front elevation view of the fiber optic ferrule push inFIG. 11;

FIG. 15 is a front elevation view of the fiber optic ferrule push inFIG. 14;

FIG. 16 is a rear perspective view of a housing for use with fiber opticassembly in FIG. 11;

FIG. 17 is a perspective view of the fiber optic assembly in FIG. 11with a housing and a slidable sleeve;

FIG. 18 a perspective view of a fourth embodiment of a fiber opticferrule push according to the present invention; and

FIG. 19 a perspective view of an adapter panel that can receive thefiber optic assemblies according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to the present preferredembodiment(s) of the invention, examples of which are illustrated in theaccompanying drawings. Whenever possible, the same reference numeralswill be used throughout the drawings to refer to the same or like parts.

Applicant notes that the term “front” or “forward” means that directionwhere the fiber optic connector and/or the ferrule would meet withanother fiber optic connector or device, while the term “rear” or“rearward” is used to mean the direction from which the optical fibersenter into the fiber-optic ferrule or fiber optic connector. Each of thefiber optic ferrules will therefore have a front and rear, and the twofronts or forward portions of the fiber optic ferrules would engage oneanother. Thus, in FIG. 1, the “front” of the fiber optic ferrule is onthe left side of FIG. 1 and “forward” is to the left and out of thepage. “Rearward” or “back” is that part of the fiber optic connectorthat is on the right side of the page and “rearward” and “backward” istoward the right and into the page

One embodiment of a fiber optic assembly 100 according to the presentinvention is illustrated in FIGS. 1-8. The fiber optic assembly 100includes a fiber optic ferrule push 102 and a fiber optic ferrule 104.The fiber optic assembly 100 may also include the housing 106,illustrated in FIG. 1. As noted therein, the fiber optic ferrule push102 and a fiber optic ferrule 104 may be inserted together into thehousing 106 from a rear end 108. A discussion of the installation of thefiber optic assembly 100 is discussed below.

The fiber optic ferrule 104 may be an MT ferrule, which is generallyknown in the art. It may also take a number of other configurations,such as those illustrated in FIGS. 2, 3, and 9. However, the fiber opticferrule 104 preferably has a main body 110 that includes a plurality ofoptical fiber support structures 112 (See also FIG. 6 and FIG. 9), whichmay be a plurality of micro-holes, v-grooves, or the like. The opticalfiber support structures 112 support and hold the optical fibers 114inserted into the fiber optic ferrule 104. The fiber optic ferrule 104may also include a window (e.g. like the window in FIG. 9) in a topsurface 118 of the fiber optic ferrule 104 to assist with the alignmentof the optical fibers 114 and to receive epoxy to secure the opticalfibers 114 therein. The main body 110 extends between a front end 120and a rear end 122, the optical fibers 114 extending from a front face124 of the front end 120 through a central opening 126 in the main body110 and exiting out the rear end 122. The rear end 122 of the main bodyalso has a rear face 128. The fiber optic ferrule 104 may also haveguide pins 130 (see FIG. 2) and/or a guide pin clamp or spacer 132disposed at the rear end 122. There may also be more than one centralopening 126 through the fiber optic ferrule 104. For example, there maybe two or more rows of optical fibers 114, optical fiber supportstructures 112 in the fiber optic ferrule 104. See FIG. 3.

The fiber optic ferrule push 102 also has a main body 150 that extendsbetween a front end 152 and a rear end 154. The main body includes acentral opening 156 that extends between the front end 152 and the rearend 154. The central opening 156 also receives the optical fibers 114that are disposed in the fiber optic ferrule 104. The front end 152 ofthe main body 150 preferably has the same dimensions of the rear end 122of the fiber optic ferrule 104. However, those dimensions of the mainbody 150 may be different from the fiber optic ferrule 104 as well.Since the optical fibers 114 are already in a ribbonized form, a heightof the central opening 156 through which the ribbonized optical fibers114 pass is preferably less than a width of the ribbon (in a transversedirection), at least at the front end 152, and possibly all throughout alength of the fiber optic ferrule push 102. Such a height prevents thefiber optic ferrule push 102 from being rotated relative to theribbonized optical fibers 114 and fiber optic ferrule 104, for example,when inside the pulling grip, and even afterwards when the fiber opticferrule 104 engages the fiber optic ferrule push 104. Preferably, thefiber optic ferrule push 102 is generally longer than the fiber opticferrule 104 (i.e., in a longitudinal direction parallel to the opticalfibers 114). Alternatively, the fiber optic ferrule push 102 may be ofsimilar length as the fiber optic ferrule 104. Regardless of the lengththereof, the fiber optic ferrule push 102 has substantially the samefootprint as the fiber optic ferrule 104, as further discussed herein.

It will be appreciated that inside the pulling grip of the fiber opticcable bundle, only the fiber optic ferrule 104 (terminated with theribbon of optical fibers 114) and the fiber optic ferrule push 102exist. Of course, several of these two components—fiber optic ferrule104 (terminated with the ribbon of optical fibers 114) and the fiberoptic ferrule push 102 exist in an optimal spatial distribution insidethe pulling sock to maximize the number of components. Alternatively,the pin clamp or spacer 132 may also be provided inside the pullingsock, but could be optional and added later after the fiber opticferrule 104 and the fiber optic ferrule push 102 have been pulled out ofthe pulling sock.

The fiber optic ferrule push 102 includes a first alignment structure160 on a top surface 162 of the main body 150. It may also be referredto as a “key” to one of ordinary skill in the art. The first alignmentstructure 160 is illustrated as a raised portion in the figures, butalso take on other configurations. As discussed below, the firstalignment structure 160 corresponds to a second alignment structure 216in the housing 106 to ensure that the fiber optic assembly 100 isinserted in correct (only in one) orientation into the housing 106. Ifthe fiber optic assembly 100 is inverted (rotated by 180°) relative tothe housing 106, the key 160 will engage a portion of the housing 106,blocking the fiber optic assembly 100 from being inserted into thehousing 106. The key 160 may take any shape or location on the fiberoptic ferrule push 102. For example, the key 160 may also be on one ofthe side surfaces 166, which are on opposing sides of the top surface162.

There may also be a window 168 extending through the top surface 162 andis in communication with the central opening 156 that forms a passagewayfor the optical fibers 114. This window 168 allows for access and/orvisual inspection by a user to the optical fibers 114.

The fiber optic ferrule push 102 has at least one projection 180 orlatch that extends from the main body 150 to engage a correspondingstructure 182 in the housing 106 (see FIG. 6). Preferably, there are twosuch projections 180, but only one may be necessary to retain the fiberoptic ferrule push 102 within the housing 106. As illustrated in figuresand perhaps best in FIG. 8, the projections 180 take the form ofcantilevered arms, that include a front chamfered surface 184 and a rearfacing flat surface 186. As the fiber optic assembly 100 (and the fiberoptic ferrule push 102 in particular) is inserted into the housing 106,the front chamfered surface 184 engages the housing 106, causing theprojection 180 to be flexed into a space 188 between the main body 150and the projection 180, thereby allowing the fiber optic assembly 100 tobe inserted into the housing 106. Once the fiber optic ferrule push 102is inserted into the housing 106 a sufficient distance, the projection180 will return to its initial position and the rear facing flat surface186 will engage the structure 182 (a window or a cavity), which has aforward facing surface 182 a in the housing 106 (see, FIG. 1). The fiberoptic assembly 100 cannot be removed from the housing 106 until andunless the projection(s) 180 is removed from the structure 182. Theprojections 180 are toward the front end 152 of the fiber optic ferrulepush 102, preferably in the front quarter thereof. It is also possiblethat the latch or projection(s) could be on the inside of the housing106 and engage a cut-out, depression or other feature on the fiber opticferrule push.

The front end 152 of the main body 150 is preferably configured toengage the rear end 122 of the fiber optic ferrule 104. The front end152 preferably has at least two raised portions 190 (a forward facingsurface) that extend from the front end 152 and away from the main body150. As illustrated in FIGS. 4 and 7-8, the raised portions 190 areelongated in the center of each of the long sides 192. These locationscorrespond to one version of the guide pin clamp or spacer 132 and allowthe raised portions 190 to directly engage the rear face 126 of thefiber optic ferrule 104. The raised portions 190 may be changed tocorrespond to a different version of a guide pin clamp or spacer.Additionally, the front end 152 may also engage the guide pin clamp orspacer directly which in turn engages the rear face 126 of the fiberoptic ferrule 104. It is desired that the fiber optic ferrule push 102engages the fiber optic ferrule 104 either directly or indirectly.

Alternatively, the raised portions 190 may instead be on the guide pinclamp 132 (albeit oppositely faced than when on the fiber optic ferrulepush 102) to engage the front end thereof. Still alternatively, when theguide pin clamp 132 is not present, the fiber optic ferrule 104 may bemodified to have the raised portions from the rear face 126 at the rearend 122 thereof. In any scenario, not all of the front end 152 of thefiber optic ferrule push 102 may engage or contact the guide pin clamp132 and/or the rear face 126 of the fiber optic ferrule 104 directly orindirectly. In yet another variation, the raised portions 190 may notexist, and may be optional to the fiber optic assembly 100.

The front end 152 may also have two recessed portions or receptacle 194to receive the rear ends of guide pins 130. The receptacle 194 ispreferably in communication with the central opening 156 and formed atleast in part by the front end 152. The central opening 156 may alsohave a ramped inner surface such that the central opening 156 is largerin cross section at the front end 152 than in a middle portion of themain body 150.

It was mentioned above that the front end 152 of the main body 150preferably has the same dimensions of the rear end 122 of the fiberoptic ferrule 104. In some embodiments, the fiber optic ferrule push 102in general may have substantially the same cross-sectional footprint asthe fiber optic ferrule 104. The term “footprint” as used in thisdisclosure refers to only height, only width, or both height and widthof the component in question (e.g., fiber optic ferrule 104 and/or thefiber optic ferrule push 102) when viewed in a cross-sectional planethat is perpendicular to a longitudinal/lengthwise axis of thecomponent. In some embodiments, the fiber optic ferrule push 102(including the key 160, the projection(s) 180, and a rear boss/flange ona side of the fiber optic ferrule push 102) may protrude no further thanor only slightly further than the footprint defined by the fiber opticferrule 104 (specifically a flange/shoulder thereof). The footprint may,for example, be less than 10% larger than that defined by the fiberoptic ferrule 104.

The housing 106 also includes, in addition to the rear end 108, a frontend 200, and an opening 202 extending between the front end 200 and therear end 108. See FIG. 1. The housing 106 also includes a key oralignment structure 210 on the outside surface 212. As with the key 160above, the key 210 prevents the housing 106 from being inserted into anadapter in the wrong orientation. It is illustrated as a rectangularstructure on a top surface 214, but it may take any shape or location onthe housing 106 so as to prevent the housing 106 from being insertedincorrectly into an adapter. The housing 106 also has a second key oralignment structure 216 in the opening 202 that aligns with and receivesthe key 160 on the fiber optic ferrule 104. In this case, the key 216 isa groove in the top of the housing 106.

As best illustrated in FIG. 6, the fiber optic ferrule push 102 extendsbeyond the rear end 108 of the housing 106 in a rearward direction.Thus, a portion of the fiber optic ferrule push 102 is not covered bythe housing 106. However, the front end 152 of the fiber optic ferrulepush 102 covered by the housing 106.

Another embodiment of a fiber optic assembly 300 is illustrated in FIGS.9 and 10. The fiber optic assembly 300 has a fiber optic ferrule push302 and a fiber optic ferrule 304. The fiber optic assembly 300 may alsoinclude the housing 306, illustrated in FIG. 9. The fiber optic ferrulepush 302 and a fiber optic ferrule 304 may be inserted together into thehousing 306 from a rear end 308.

The fiber optic ferrule 304 may also be an MT ferrule as described aboveor have another configuration and structure. However, the fiber opticferrule 304 preferably has a main body 310 that includes a plurality ofoptical fiber support structures 312, which may be a plurality ofmicro-holes, v-grooves, or the like. The optical fiber supportstructures 312 support and hold the optical fibers 114 inserted into thefiber optic ferrule 304. The fiber optic ferrule 304 may also include awindow 316 in a top surface 318 of the fiber optic ferrule 304 to assistwith the alignment of the optical fibers 114 and to receive epoxy tosecure the optical fibers 114 therein. The main body 310 extends betweena front end 320 and a rear end 322, the optical fibers 114 extendingfrom a front face 324 of the front end 320 through a central opening 326in the main body 310 and exiting out the rear end 322. The fiber opticferrule 304 may also have guide pins 330 (see FIG. 2) and/or a guide pinclamp or spacer 132 disposed at the rear end 322. There may also be morethan one central opening 326 through the fiber optic ferrule 304. Forexample, there may be two or more rows of optical fibers 114, opticalfiber support structures 312 in the fiber optic ferrule 304.

The fiber optic ferrule push 302 also has a main body 350 that extendsbetween a front end 352 and a rear end 354. The main body 350 includes acentral opening 356 that extends between the front end 352 and the rearend 354. The central opening 356 also receives the optical fibers 114that are disposed in the fiber optic ferrule 304. The front end 352 ofthe main body 350 preferably has the same dimensions of the rear end 322of the fiber optic ferrule 304. However, those dimensions of the mainbody 350 may be different from the fiber optic ferrule 304 as well. Thefiber optic ferrule push 302 generally cannot rotate much relative tothe optical fibers 114 and the fiber optic ferrule 304.

The fiber optic ferrule push 302 includes a first alignment structure360 on a top surface 362 of the main body 350. It may also be referredto as a “key” to one of ordinary skill in the art. The first alignmentstructure 360 is illustrated as a raised portion in the figures, butalso take on other configurations. As discussed below, the firstalignment structure 360 corresponds to a second alignment structure (thesame as 216 in FIG. 1) in the housing 306 to ensure that the fiber opticassembly 300 is inserted in correct (only in one) orientation into thehousing 306. If the fiber optic assembly 300 is inverted or flipped by180° relative to the housing 306, the key 360 will engage a portion ofthe housing 306, blocking the fiber optic assembly 300 from beinginserted into the housing 306. The key 360 may take any shape orlocation on the fiber optic ferrule push 302. For example, the key mayalso be on one of the side surfaces 366, which are on opposing sides ofthe top surface 362.

The fiber optic ferrule push 302 has at least one projection 380 thatextends from the main body 350 to engage a corresponding structure 382 ain the housing 306. Preferably there are two such projections 380, oneon the top and one on the bottom (see FIG. 10). However, only one may benecessary to retain the fiber optic ferrule push 302 within the housing306. As illustrated in figures, the projections 380 take the form ofcantilevered arms, that include a front chamfered surface 384 and a rearfacing flat surface 386. As the fiber optic assembly 300 (and the fiberoptic ferrule push 302 in particular) is inserted into the housing 306,the front chamfered surface 384 engages the housing 306, causing theprojection 180 to be flexed into the central opening 356, therebyallowing the fiber optic assembly 300 to be inserted into the housing306. Once the fiber optic ferrule push 302 is inserted into the housing306 a sufficient distance, the projection 380 will return to its initialposition and the rear facing flat surface 386 will engage the structure382 (a window or a cavity), which has a forward facing surface 388. Thefiber optic assembly 300 cannot be removed from the housing 306 untiland unless the projection(s) 380 is removed from the structure 382. Theprojections 380 are toward the rear end 354 of the fiber optic ferrulepush 302, preferably in the rear quarter thereof.

The front end 352 of the main body 350 is preferably configured toengage the rear end 322 of the fiber optic ferrule 304. The front end352 preferably has at least two raised portions 390 that extend from thefront end 352 and away from the main body 350. As in the priorembodiment, the raised portions 390 are elongated in the center of eachof the long sides 392. These locations correspond to one version of theguide pin clamp or spacer 132 and allow the raised portions 390 todirectly engage the rear end 322 of the fiber optic ferrule 304. Theraised portions 390 may be changed to correspond to a different versionof a guide pin clamp or spacer. Additionally, the front end 352 may alsoengage the guide pin clamp or spacer directly which in turn engages therear end 322 of the fiber optic ferrule 304. It is desired that thefiber optic ferrule push 302 engages the fiber optic ferrule 304 eitherdirectly or indirectly.

Another embodiment of a fiber optic assembly 400 is illustrated in FIGS.11-17. The fiber optic assembly 400 has a fiber optic ferrule push 402and a fiber optic ferrule 404. The fiber optic assembly 400 may alsoinclude the housing 406, illustrated in FIG. 16. The fiber optic ferrulepush 402 and a fiber optic ferrule 404 may be inserted together into thehousing 406 from a rear end 408.

The fiber optic ferrule 404 may the same as in the prior embodiment, andonly relevant structures will be described herein with respect to fiberoptic ferrule 404. The fiber optic ferrule push 402 is a tool-less fiberoptic ferrule push in that no tools are required to remove the fiberoptic ferrule push 402 from the housing 406 as the first embodiment. Inthat embodiment, a tool would be needed to disengage the projections 480from the housing 106. However, fiber optic ferrule push 402 can beremoved by simply squeezing the rear end 454. For example, the ends of ashoulder 458 may be squeezed toward each other to reduce a centralopening 456.

The fiber optic ferrule push 402 has a main body 450 that extendsbetween a front end 452 and a rear end 454. The main body 450 includesthe central opening 456 that extends between the front end 452 and therear end 454. The central opening 456 also receives the optical fibers114 that are disposed in the fiber optic ferrule 404. The height of thecentral opening 456 at the front end 452 is also preferably less thantwo times the diameter of the optical fibers 114 to also prevent thefiber optic ferrule push 402 from being rotated relative to the opticalfibers 114 and fiber optic ferrule 404. The rear end 454 has an enlargedportion or shoulder 458, which allows for the user to more easily graspthe rear end 454. As illustrated in FIG. 17, the rear end 454 and theshoulder 458 extend beyond the rear end 408 of the housing 406 in arearward direction

The fiber optic ferrule push 402 has a top side 434 and a bottom side436, which are separated by two side walls 466. In the top side 434 is aslot 438 that extends from the front end 452 to the rear end 454. Theslot 438 is in communication with the central opening 456. The fiberoptic ferrule push 402 also has at least one projection 480 that extendsfrom the main body 450. While one projection 480 may be sufficient toretain the fiber optic ferrule push 402 in the housing 406, there arepreferably two projections 480. In this embodiment, the projections 480extend from the side walls 466 and are closer to the rear end 454 thanthe front end 452. In fact, the projections 480 are in the back quarterof the main body 450.

The bottom side 436 of the fiber optic ferrule push 402 is illustratedin FIG. 13. There is a second slot 440 that extends from the rear end454 towards the front end 452, but stops short thereof. The second slot440 is also narrower than the slot 438 on the top side 434. The secondslot 440 is also in communication with the central opening 456. The slot438 and the second slot 440 cut the shoulder 458 into two sections. Whena user presses the two sections of the shoulder 458 together, then theprojections 480 are released from a corresponding structure (e.g., awindow or a cavity) in the housing 406. Thus, no tools are needed toremove the fiber optic ferrule push 402. The slot 438 providescompliance or flexibility to the fiber optic ferrule push 402. In analternative embodiment, the slot 438 may be optional.

The fiber optic ferrule push 402 includes a first alignment structure460 on the bottom side 436 of the main body 450. It may also be referredto as a “key” to one of ordinary skill in the art. The first alignmentstructure 460 is illustrated as a raised portion in the figures, but mayalso take on other configurations and locations as noted above. Thefirst alignment structure 460 corresponds to a second alignmentstructure 416 in the housing 406. See FIG. 16. If the first and secondalignment structures do not align, then the fiber optic assembly 400will not fit within the housing 406.

Turning to FIGS. 14 and 15, the front end 452 will be discussed. Thefront end 452 has two different forward facing surfaces 442, 444. Thefirst forward facing surface 442 is farther forward than the secondforward facing surface 444. The first forward facing surface 442 isgenerally smaller (thinner) and extends around the second forward facingsurface 444. The first forward facing surface 442 may engage the rearfacing portion of a fiber optic ferrule 404 as illustrated in FIG. 11.The second forward facing surface 444 may engage the rear face of thefiber optic ferrule 404. It is possible that both the first and thesecond forward facing surfaces 442, 444 engage the fiber optic ferrule404. The second forward facing surface 444 may also two recessedportions or receptacles 494 to receive the rear ends of guide pins. Thereceptacles 494 are preferably in communication with the central opening456.

FIG. 17 illustrates fiber optic assembly 400 inserted into the housing406, which may also have a slidable sleeve 498 that is placed around atleast a portion of the housing 406. Similar to typical MPO connectors,the slidable sleeve 498 is movable or slidable relative to the housing406. As illustrated, and similar to other embodiments, a portion of thefiber optic ferrule push 402 is outside the housing 406.

Another embodiment of a fiber optic ferrule push 502 is illustrated inFIG. 18. In this embodiment, which is similar to that in FIGS. 11-17,the fiber optic ferrule push 502 has at least one projection 580 thatextends from the main body 550. While one projection 580 may besufficient to retain the fiber optic ferrule push 502 in the housing,there are preferably two projections 580. In this embodiment, theprojections 580 extend from the side walls 566 and are closer to thefront end 552 than the back end 554. In fact, the projections 580 arepreferably in the front quarter of the main body 550.

FIG. 19 illustrates one embodiment of an adapter panel 600 that includesa plurality of adapters 602 that are installed in the adapter panel 600.The adapters 602 removably receive the housings (e.g., 106, 306, 406),which in turn receive the fiber optic assemblies, including the fiberoptic ferrules (e.g., 104, 204, etc.). The fiber optic ferrule push mayremain attached to the housing or may be removable from the fiber cable,e.g., in the embodiments shown in FIGS. 9-17 and 18. For example, thefiber optic ferrule push may slide back on the ribbonized optical fiberand simply rest thereupon when not in use.

As noted above, the size of the conduits through which the opticalfibers pass, as well as the sizes of the pulling socks, are limited.Therefore, it is preferable to have the fiber optic connectors andcomponents be as small as possible to allow for as many terminatedoptical fibers as possible within the pulling sock. Further, the variousembodiments can reduce the number of components required in making anoptical connection. One way to do this is to eliminate the outerhousings (such as housings 106, 406, etc.) which take up a lot ofvolume, until the optical fibers have been passed through conduits. Suchhousings can thereafter be installed to complete the assembly of theoptical connectors. As an alternative, it is possible for the housingsto be pre-installed into adapters that are disposed within the adapterpanel 602 (e.g., shown in FIG. 19). With the fiber optic assemblydisclosed herein, it is possible to simply plug the fiber opticassemblies directly into the pre-installed housings on the adapters 602to simultaneously complete installation optical connectors on theassociated cable (ferrules and outer housings installed) andinstallation of the optical connectors in the adapters 602. The fiberoptic assemblies are disposed within the housings from the rear thereof.See FIG. 1. Thus, once the fiber optic assemblies are removed from thepulling sock, they can be pushed into the housings using the fiber opticferrule push (e.g., 102, 402, 502). Typical MPO connectors may bealready provided on the opposite side of the adapters 602 that connectto various equipment inside a data center. This procedure of connectingfibers in the fiber optic ferrule eliminates the need to perform thefusion splicing of the optical fibers at the point where the fiber opticcable bundles from another data center enter a data center, andtherefore the time and complexity of the installation needed to turnconnect two data centers is reduced significantly. Since the fiber opticferrule push has substantially the same footprint as the fiber opticferrule inside the pulling sock, no significant changes to the pullingsock are required. Therefore, various embodiments of the fiber opticferrule push as disclosed herein retroactively fit into the currentpulling socks used in the field by the fiber optic connection industry.The housings could have a dust plug or some other structure to protectthe inside portions of the housings from dust and debris. Similarly, theback side of the panel that has the adapters could also have dust plugs,to prevent dust and debris from fouling the faces of previouslyinstalled fiber optic assemblies. The fiber optic assembly disclosedherein may be provided as a bag of parts or a kit with the componentsshown in FIGS. 1-19. A cable assembly house or an end user at a datacenter may then use these components to achieve the setup shown herein.

Accordingly, various embodiments of the invention provide a method ofconnecting two or more data centers in an automated or “turn-key”manner, without requiring days or weeks of manual fusion splicing andminimal human labor. Since the components are manufactured to precision,errors due to human handling of fibers during splicing are alsoeliminated or substantially reduced. This method includes a step ofconnecting a fiber optic ferrule (e.g., the fiber optic ferrule 104) toan MPO connector by providing the fiber optic ferrule 104 in a pullinggrip of a jacketed fiber optic cable. The fiber optic ferrule 104 has atleast one optical fiber terminated therein. Preferably, the fiber opticferrule 104 is a multi-fiber ferrule, although single fiber ferrulescould also be used with a smaller fiber optic ferrule push than the onedisclosed herein. The method includes installing the ferrule push at aback side of the fiber optic ferrule. The fiber optic ferrule push isgenerally free of the fiber optic ferrule, except when used to push thefiber optic ferrule. The method includes installing a housing (e.g., thehousing 106) at least partially surrounding the fiber optic ferrule andthe ferrule push, the housing being insertable into an adapter (e.g.,one or more of the adapters 602) in a panel (e.g., the adapter panel600.

To install the fiber optic ferrule to the pre-populated adapters 602,the method includes pulling the fiber optic ferrule out of the pullinggrip, and pushing the ferrule into the housing using the fiber opticferrule push after said pulling.

It will be apparent to those skilled in the art that variousmodifications and variations can be made to the present inventionwithout departing from the spirit and scope of the invention. Thus it isintended that the present invention cover the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

We claim:
 1. A fiber optic ferrule push comprising: a main bodyextending between a front end and a rear end, the main body having acentral opening extending between the front end and the rear end toreceive a plurality of optical fibers therethrough; a front facingsurface at the front end of the main body configured to engage a rearsurface of a fiber optic ferrule; at least one projection extendingoutward from the main body to engage a housing configured to receive thefiber optic ferrule; and a key extending outward from a surface of themain body.
 2. The fiber optic ferrule push according to claim 1, whereinthe front facing surface is a first front facing surface and the frontend of the main body has a second front facing surface, the second frontfacing surface disposed parallel to and rearward of the first frontfacing surface.
 3. The fiber optic ferrule push according to claim 1,wherein the at least one projection comprises two projections, theprojections being disposed on opposing sides of the main body of thefiber optic ferrule push.
 4. The fiber optic ferrule push according toclaim 3, wherein the key is on a top of the main body, the top disposedbetween two sides, each of the sides having one of the two projections.5. The fiber optic ferrule push according to claim 1, wherein the atleast one projection is at an end of an arm extending from a side of themain body.
 6. The fiber optic ferrule push according to claim 1, whereinthe key is matched to an epoxy window of a fiber optic ferrule securedto the plurality of optical fibers passing through the main body.
 7. Thefiber optic ferrule push according to claim 1, wherein the at least oneprojection is disposed in a front quarter of the main body.
 8. The fiberoptic ferrule push according to claim 1, wherein the front end of themain body has a recessed portion, the recessed portion having the frontfacing surface and at least a second front facing surface.
 9. The fiberoptic ferrule push according to claim 1, wherein the front end has atleast one receptacle to receive a portion of a guide pin disposed withina fiber optic ferrule associated with the fiber optic ferrule push. 10.The fiber optic ferrule push according to claim 1, wherein the main bodyhas a slot in one surface, the slot extending from the front end to therear end.
 11. The fiber optic ferrule push according to claim 10,wherein the at least one projection is disposed in a rear quarter of themain body.